Wrench for crimping connectors



May 4, 1965 H. H. ESSER WRENCH FOR CRIMPING CONNECTORS Filed Dec. 1, 1961 2 Sheets-Sheet? INVENTUR. B f/aro/o H [me/3 ark 5 flme/ Ail omega United States Patent 3,181,339 WRlENtCl-ll FUR (IRlMllNG CGNNECTQRS Harold H. Esser, Clricago, Ill, assignor to Ideal industries, Inc, Sycamore, ill, a corporation of Delaware Filed Dec. ll, 1%1, Ser. No. 156,229 Claims. (Cl. 712-402) This invention is directed to crimping tools, in particular, a tool for impressing multiple crimps in connectors for electric wires, electric cables and the like.

The use of connectors in the electric art is widely practiced. Such connectors most often take the form of hollow cylindrical sleeves made out of metal or plastic. They are placed in operation by inserting the ends of electric wires and the like in close association with the internal walls of the sleeve, and thereafter crimping means are employed to force the walls against the ends of the wires in pressure tight relationship. It is often desired to impress a series of crimps in one connector, and this has been accomplished by multiple operations with crimping tools.

It is a primary object of my invention to provide a crimping tool which operates efliciently and quickly to impress crimps on connectors.

Another object of my invention is to provide a tool having multiple crimping means for impressing a series of crimps in connector sleeves and the like in one operation.

A still further object of my invention is to provide a tool which is conveniently operated by reciprocal movements to quicl y impress connector sleeves and the like with crimping means.

A further object is a crimping tool which can be easily and quickly disconnected to allow facile removal of the crimp connector sleeve.

A further object is a crimping tool whereby equally strong forces are directed against crimping elements to eificiently impress connector sleeves and the like.

Another object is a manually operated crimping tool which can be economically manufactured to crimp connector sleeve sand the like.

Another object is a crimping tool with indirectly actuated mechanical means for obtaining a uniformly strong impress in connector sleeves and the like.

Another object is a crimping tool of the above type with a high mechanical advantage which can be operated with one hand.

Another object is a crimping tool for applying multiple crimps constructed so that the unit pressure applied by the dies may be controlled, for example, made the same, balanced, or set in any suitable or desired ratio, depending upon the work and application involved.

The foregoing objects and other objects are accomplished by the crimping tool which is described in detail in the following description and in the attached drawings. Reference will be made to the drawings wherein:

FIGURE 1 is a front view of partially removed fragments showing the actuating mechanism,

FIGURE 2 is a side elevation View of the crimping tool,

FIGURE 3 is a side View taken in cross section and viewed along lines 33 of FIGURE 1,

FIGURE 4 is a front view taken along lines 4-4 of FIGURE 2 with the outer shell removed to show the pawl and ratchet mechanism,

FlGURE 5 is another front view along lines S-5 of FIGURE 3 showing the cam surfaces coacting with the crimping elements,

FIGURE 6 is a side view, similar to FIGURE 2, but in full, and

FIGURE 7 is an enlarged view of modified dies.

Reference to FIGURE 1 shows a handle means I coextensively joined to a housing 2. The housing 2 is covered by a front cover 3 and a back cover 3. The covers 3 and 3' can be reciprocally moved around the housing 2 by reciprocally actuating extending handle 4 inwardly and outwardly. The handles 1 and 4 are shown gapped by a coil spring 5 directed towards returning the handle 4- to an outward position. The covers 3 and 3' have openings so that together with the housing 2 a common pasasgeway ll is present wherein a connector sleeve is inserted into a crimping station for crimping action by the elements or dies 12 and 13.

in FIGURE 5, the housing 2 with its central passageway is clearly seen. The walls of the housing 2 are shaped to form two or more diametrically opposed cam surfaces 15 and 15. Within the housing 2 is the crimping station wherein is present an annular die carrier 16 having a central open portion common with the passageway lti. The annular carrier 16 has slots 17 spaced to receive in close sliding relationship a pair of crimping elements or dies 13 and 12 towards the front of the housing 2, and another pair of crimping elements 13 and 12 towards the back of the housing 2. The crimping elements or dies l2, l3 and 12', 13 are biased outwardly against the cam surfaces 15 and 15' by leaf springs 13 and id which are shown seated in the back portion of the crimping elements 12 and 13 and secured by screws 1% and 19 in the annular die carrier 16.

For purposes of convenience in this description, the crimping tool will be referred to as having a front side which is the side having the ratchet and pawl means shown in FIGURE 4 and a back side which is the opposite side. The annular die carrier 16 is held in a freely rotatable manner in housing 2 by an annular guide band it; on the front side and an annular guide band 2% on the back side. The annular guide band 2*!) has an outer circumference which is immovably fixed in a groove of the housing 2 by pins 21. The inner circumference of the annular guide band is freely adjoined to the annular carrier 16. The annular guide band 20 on the front side and annular guide band ill on the back side similarly connect the annular die carrier 16 to the housing 2. The foregoing ar rangement enables annular carrier 16 to be freely rotatable within the housing 2 and permits the crimping elements or dies l2, l3 and l2, 13 carried by the slots 17 of the annular die carrier 16 to coact with the cam surfaces 15 and 15'. FIGURE 3 shows such crimping elements in fully closed position with their crimping means interacting as indicated by the dotted lines located intermediate the crimping elements 12, 13 and 12, 13'. To attain this fully closed position, the back portions of the crimping elements are progressively directed towards the high point of the cam surface 15 and 15', thereby radially forcing the crimping dies l2, l3 and l2, 13 towards one another. By freely rotating the annular die carrier 16 within the housing 2, it is now seen how the crimping elements i2, 13 and 12', 13' are slidably changed along a radial path from a fully opened position, as shown in FIG- URE 5, to a fully closed position, as shown in side section view in FIGURE 3.

The rotating of the annular die carrier 16 is accomplished by a pawl and ratchet means as shown in FIGURE 4. One or more pawls 25 are placed to coact with the teeth 27 of a ratchet plate 26. The ratchet plate 26 is secured to the annular carrier 15 by screws 26. The pawls 25 are pivoted at 28 to the underside of the front cover 3. The pawls 25 are biased inwardly against the teeth 27 of the ratchet plate 26 by springs 29. The covers 3 and 3' are on the front and back sides of the crimping tool. An integral extension of the covers 3 and 3' on both the front and backsides assumes the form of handle means i. The front and back covers 3 and 3 can be joined by a continuous annular band to form one complete integral unit or can alternatively be joined by a plurality of spaced members. Other equivalent means will be apparent to those skilled in the art.

The edges of the openings in the front and back covers 3 and 3 are in rotatable registration with an annular spacer band 3% on the front side and an annular spacer band 36' on the back side. This allows reciprocal movement of the front and back covers 3 and 3' by working the handle 4. The annular spacer band 36) is superimposed on the ratchet plate 26 and afiixed thereto on the front side. The annular spacer 39' is aflixed directly on the annular carrier 16 on the back side. The foregoing annular spacer bands have central openings so as to continue the presence of the common passageway 10. The front and back covers 3 and 3' also have central openings with dimensions that allow its annular edges to be rotatably registered with the side walls of the annular spacer bands 30 and 36', as shown in FIGURE 3. The covers 3 and 3' can be partly covered by an outer plate 32 on the front side and an outer plate 32' on the back side. The outer plate 32 will, of course, have a central open portion to continue the presence of the central passageway and to allow entrance of the connector sleeve for crimping action by the elements or dies 12, 13 and 12', 13'.

The pivot 28 of the pawls 25 is made to the underside of the front cover 3 as shown in FIGURE 2 and FIGURE 3. It is thus seen how reciprocal inward and outward movement of the handle 4 actuates the pawls 25 against the teeth 27 of the ratchet plate 26 to effect rotatable motion of the underlying annular die carrier 16. The rotatable motion occurs counterclockwise in the instant illustration. The pawls 25 normally engage the teeth 27 of the ratchet plate 26 as a result of the inward spring bias achieved by spring 29. The pawls 25 are separated from such engagement by holding pins 33 imbedded in the annular spacer band 28. To separate the pawls 25 from engagement with the teeth 27 of ratchet plate 26, the handle 4 is moved outwards to fully extended position; thus, the projecting bill 34 intercepts the holding pin 33 to pivotally turn the pawl 25 away from engagement with teeth 27.

In FIGURE 6, a stop 27' may be provided on the front cover 3 which, when it hits the handle 1, determines the maximum open position of handles 1 and 4.

The dimensioning of the cam surfaces and 15 and the dies 12 and 13 may be such that the opposed faces of the dies will not contact before the outer ends of the dies drop off the high cam surfaces to the adjoining low cam surfaces. Or I may mount positive stops on the high cam surfaces to prevent die ends from going by.

The crimping tool is usefully employed by inserting a connector sleeve with the wires placed therein in the passageway 10 between the crimping means on the crimping elements or dies 12, 13 and 12, 13'. The handle 4 is then reciprocally moved in and out and this movement actuates successive engagements of the pawl with the teeth 27 of the ratchet plate 26. The actuated ratchet plate 26 rotates the underlying annular die carrier 16 secured thereto counterclockwise and the crimping elements 12, 13 and 12', 13 are gradually forced toward one another along a radial path as the back portions of the crimping elements progress onto the high point of the cam surfaces 15 and 15'. The reciprocal motion of the handle 4 is continued until the connector sleeve is crimped by the crimping elements or dies in closed position. Following the satisfactory production of the crimp, the handle 4 is moved outward to fully opened position thereby causing the holding pin 33 to intercept the projected bill 34 on the pawl 25 and thereafter pivotally force the pawl 25 to separate from the teeth 27 of the ratchet plate 26. When the handle 4 is in full open outward position, the pawl 25 is separated from the teeth 27, and it is then possible to freely rotate the ratchet plate and the atiixed annular die carrier 16 clockwise until the crimping elements or dies (a, 12, 13 and 12, 13 are again returned to fully open position as shown in FIGURE 5.

In FIGURE 7, I have shown a modified form of die composed of two parts, an inner part 35 and an outer part 36. They socket together at 37 and a fibrous or resilient washer 38 or the like may be positioned between them, held in place by a pin or brad 39. In this case, the Washer may be a fabric or leather or a plastic or any suitable material which will compress and/ or distort under pressure but will return to its original shape when released. The die in FIGURE 7 may be considered to be any one of the four dies shown in FIGURE 2, for example. Or I may apply the compressible washer to only two dies, one in each set.

Be that as it may, the object is to keep the unit pressure of each set of dies equal or balanced or related to each other in some selected ratio. Otherwise, one set of dies may take all or most of the load under particular circumstances.

For example, when the wires to be connected are twisted together, the resistance offered to one set of dies may be substantially more or less than to the other set, due to wire orientation. Assuming that dies 12 and 13 take most of the load, a fibrous or plastic washer, as at 38, in either one or both dies 12 and 13, will compress or distort somewhat allowing the other set of dies 12' and 13 to close against and crimp the sleeve.

I have stated that the object is to balance the unit pressure or otherwise control the ratio of the unit pressure between die sets. And it should be understood that I may deliberately unbalance the unit pressure so that one set of dies will automatically apply more thrust due to a higher unit pressure than the other. This could be done quite easily by having a washer or washers in one set and'none on the other. Or the washer or washers in one set could have a higher compressive strength or modulus of elasticity than the other.

I have shown a washer or insert, but it should be understood that I might use a leaf spring, a coil spring, a washer or Belleville spring or otherwise. In a sense, it might be considered a lost motion connection which evens out or balances or ratios the unit pressure between two die sets.

This same balancing or ratioing of unit pressures of die sets between a double crimp situation can be used in hand crimpers, bench crimpers or otherwise. In a more sophisticated bench crimper or automatic crimping tool, it should be understood that the unit pressures may be ratioed hydraulically. For example, the pistons moving the dies could be the same or different sizes, depending upon the ratio desired. Also, this might be done mechanically by a load dividing yoke or bridge straddling the outer ends of the dies, set at any suitable ratio.

It will be seen from the foregoing description and drawings that a crimp of uniform impression can be made in connector sleeves with the crimping tool. Mechanically actuated means can make such a uniform impression independent of manual squeezing force in the usual hand operation. A particular advantage of the crimping tool is its action of impressing multiple crimps in a single operation. This is a favorable contrast to prior art tools which require multiple manual operations to impress a series of single crimps.

The crimping tool can be modified in many of its features to accommodate particular crimping operations involving connector sleeves of various sizes, shapes and materials. Plurality of crimping elements can be incorporated in the annular carrier 16 to effect a variety of crimping impressions. It is, of course, apparent that a wide variety of crimping surfaces can be provided on the faces of the crimping elements.

Within the many possible modifications, I include those crimping tools which have particular spacing of the teeth 27 on the ratchet plate 26 so that the crimping elements 12 and 13 assume a close position of desired spacing for J a particular connector sleeve of given dimensions. It is also intended that the common passageway can have various opening sizes to also accommodate connector sleeves of different dimensions.

The foregoing invention can now be practiced by those skilled in the art. Such skilled persons will know that the invention is not necessarily restricted to the particular embodiments presented therein. The scope of the invention is to be defined by the terms of the following claims as given meaning by the preceding description.

I claim:

1. In a crimping tool for crimping sleeves for forming electrical connections, a cylindrical housing having a central passageway defining a crimping station in the housing to receive such sleeves, diametrically opposed cam surfaces on the inner wall of said housing, an annular die carrier freely rotatably positioned in the housing and spaced from the cam surfaces, a plurality of opposed crimping dies slidably seated in the carrier, said dies extending from the central opening of said annular die carrier to the outer periphery thereof and engaging said cam surfaces, a ratchet fixed to the carrier on the front side, front and back covers rotatably mounted on the housing and having central openings registering with the central opening in the annular die carrier, pawls pivotally joined to the front cover and biased by springs to engage the ratchet means to actuate the pawl and ratchet whereby reciprocal movements of said means rotate the die carrier so that the crimping dies are forced inwards as they engage the high points of the cam surfaces, and intercepting means to effect separation of the pawls from the ratchet when the handle is moved fully in one direction.

2. In a crimping tool for crimping sleeves for forming electrical connections, a housing having a central passageway defining a crimping station in the housing to receive such sleeves, diametrically opposed cam surfaces on the inner walls of said housing, an annular die carrier freely rotatably positioned in the housing and spaced from the cam surfaces, a pair of opposed crimping dies slidably seated in the carrier, another pair of opposed crimping dies slidably seated in the carrier, said dies extending from the central opening of said carrier to the outer periphery thereof and engaging said cam surfaces, guides fixed to the housing on the front and back sides and having central openings registering with central openings of the carrier, a ratchet fixed to the carrier on the front side, a spacer fixed to the ratchet and another spacer fixed to the carrier on the back side, front and back covers having central opening registering with openings in the spacers and rotatably mounted with respect to the housing, pawls pivotally joined to the front cover and biased by springs to engage the ratchet, means to reciprocally rotate the front cover whereby reciprocal movements of the front cover actuate the pawl and ratchet to rotate the die carrier so that the crimping dies are forced inwards as they engage the high points of the cam surfaces, and holding pins immovably situated to intercept projections on said pawls to effect separation of the pawls from the ratchet when the front cover is moved fully in one direction.

3. In a crimping tool for crimping sleeves for forming electrical connections, a housing with front and back sides and a central passageway therethrough defining a crimping station in the housing to receive such sleeves, opposed cam surfaces on the inner Walls of said housing, an annular die carrier freely rotatably positioned in the housing, crimping dies oppositely disposed and slidably seated in the carrier, said crimping dies having a working face disposed in the central opening of the carrier and a cam follower face engaging said cam surfaces, said dies outwardly biased against the cam surfaces, a ratchet fixed to the carrier on the front side, a front cover rotatably mounted on said housing, means to reciprocally rotate the cover, pawl pivotally joined to the front cover and biased to coact with the ratchet, and intercepting means located adjacent the pawl to effect separation of the pawl from the ratchet when the front cover is moved fully in one direction.

4. In a crimping tool for crimping sleeves for forming electrical connections, a housing, a passageway in the housing defining a crimping station to receive such sleeves with wires therein, at least two sets of opposed compressible crimping dies mounted in the housing at the crimping station, means movably carrying said dies, means to move the opposed sets of dies together to effect a crimping action, each of said dies having a first part to contact the means to move the dies, a socket in said first part, a second part having a crimping face, said second part freely and slidably received in said socket, an intermediate resilient part seated in the bottom of the socket, and said parts connected together so that the unit pressure between opposed dies tends to balance during the crimping operation.

5. In a crimping tool for crimping sleeves for forming electrical connections, a housing, a central passageway defining a crimping station in the housing to receive such sleeves with wires therein, cam surfaces on the inner walls of said housing, at least one set of compressible crimping dies opposed to another set of compressible crimping dies in the housing, means to movably hold the dies, each of said crimping dies having an upper cam follower engaging the cam surfaces, a socket in said cam follower, a part with a crimping face, said crimping face part freely and slidably received in the socket of the cam follower and an intermediate resilient part seated in the bottom of the socket, said cam follower and parts connected together so that the unit pressure tends to balance during the crimping operation, and means for creating rotary motion between the dics and the cam surfaces such that operation thereof will force the dies inwardly into the central passageway.

References Cited by the Examiner UNITED STATES PATENTS 2,079,498 5/37 Douglas. 2,409,549 10/46 Djidics. 2,753,742 7/56 Buchanan. 2,861,491 11/58 Rozmus. 2,898,790 8/59 Lazar et al. 2,928,299 3/60 Fuller. 3,028,776 4/62 Keller et al.

WILLIAM FELDMAN, Primary Examiner.

WALTER A. SCHEEL, Examiner. 

1. IN A CRIMPING TOOL FOR CRIMPING SLEEVES FOR FORMING ELECTRICAL CONNECTIONS, A CYLINDRICAL HOUSING HAVING A CENTRAL PASSAGEWAY DEFINING A CRIMPING STATION IN THE HOUSING TO RECEIVE SUCH SLEEVES, DIAMETRICALLY OPPOSED CAM SURFACES ON THE INNER WALL OF SAID HOUSING, AN ANNULAR DIE CARRIER FREELY ROTATABLY POSITIONED IN THE HOUSING AND SPACED FROM THE CAM SURFACES, A PLURALITY OF OPPOSED CRIMPING DIES SLIDABLY SEATED IN THE CARRIER, SAID DIES EXTENDING FROM THE CENTRAL OPENING OF SAID ANNULAR DIE CARRIER TO THE OUTER PERIPHERY THEREOF AND ENGAING SAID CAM SURFACES, A RATCHET FIXED TO THE CARRIER ON THE FRONT SIDE, FRONT AND BACK COVERS ROTATABLY MOUNTED ON THE HOUSING AND HAVING CENTRAL OPENINGS REGISTERING WITH THE CENTRAL OPENING IN THE ANNULAR DIE CARRIER, PAWLS PIVOTALLY JOINED TO THE FRONT COVER AND BIASED BY SPRINGS TO ENGAGE THE RATCHET MEANS TO ACTUATE THE PAWL AND RATCHET WHEREBY RECIPROCAL MOVEMENTS OF SAID MEANS ROTATE THE DIE CARRIER SO THAT THE CRIMPING DIES ARE FORCED INWARDS AS THEY ENGAGE THE HIGH POINTS OF THE CAM SURFACES, AND INTERCEPTING MEANS TO EFFECT SEPARATION OF THE PAWLS FROM THE RATCHET WHEN THE HANDLE IS MOVED FULLY IN ONE DIRECTION. 